[Treatment of recurrent laryngeal papilloma by submucosal resection and the effect on prognosis]

OBJECTIVE

To investigate the efficacy of submucosal resection by CO2 laser in the treatment of recurrent laryngeal papilloma and the effect on prognosis.

METHOD

A total of 11 patients diagnosed as recurrent laryngeal papilloma were included in this review. Papilloma was marked before operation and checked under fibro-laryngoscope. Papilloma was resected completely including the submucosal tissure with CO2 laser or microequipment. In widespread papilloma, false membrane in raw surface were cleared 7-10 days after operation. Surgical specimens (including membrane) were detected by routine pathology, HPV typing and immunohistochemical pathologic examination. The patients were checked once a month in the first 3 months after operation, and then once for every 3 months. Once the hoarseness and other symptoms aggravated or the disease was recurrent, the patients were treated immediately.

RESULT

HPV viral DNA was found in 10/11 cases, with HPV11 (7/11 cases) and HPV6 (3/11 cases). Cases with regards to follow-up, from 6 months to 1 year, 3 cases were followed up 1 year after operation, without recurrence. Five patients including 2 children were followed up 6 to 12 months after operation, without recurrence. Two children underwent 2 or 3 operations, were followed-up more than 6 months withouting recurrence.

CONCLUSION

Papilloma submucosal resection could decrease postoperative recurrence and is worth to be further investigated.

Programmable Laser-Assisted Surface Microfabrication on a Poly(Vinyl Alcohol)-Coated Glass Chip with Self-Changing Cell Adhesivity for Heterotypic Cell Patterning

Organs are composed of heterotypic cells with patterned architecture that enables intercellular interaction to perform specific functions. In tissue engineering, the ability to pattern heterotypic cells into desired arrangement will allow us to model complex tissues in vitro and to create tissue equivalents for regeneration. This study was aimed at developing a method for fast heterotypic cell patterning with controllable topological manipulation on a glass chip. We found that poly(vinyl alcohol)-coated glass showed a biphasic change in adhesivity to cells in vitro: low adhesivity in the first 24 h and higher adhesivity at later hours due to increased serum protein adsorption. Combining programmable CO2 laser ablation to remove poly(vinyl alcohol) and glass, we were able to create arrays of adhesive microwells of adjustable patterns. We tested whether controllable patterns of epithelial-mesenchymal interaction could be created. When skin dermal papilla cells and fibroblasts were seeded respectively 24 h apart, we were able to pattern these two cells into aggregates of dermal papilla cells in arrays of microwells in a background of fibroblasts sheet. Seeded later, keratinocytes attached to these mesenchymal cells. Keratinocytes contacting dermal papilla cells started to differentiate toward a hair follicle fate, demonstrating patternable epithelial-mesenchymal interaction. This method allows fast adjustable heterotypic cell patterning and surface topology control and can be applied to the investigation of heterotypic cellular interaction and creation of tissue equivalent in vitro.

[Application of CO2 laser and self-made laryngeal dilator in the treatment of the laryngeal stenosis]

OBJECTIVE

To study the treatment effect of CO2 laser and self-made laryngeal dilator on the laryngeal stenosis.

METHOD

Twenty-five patients with laryngeal stenosis were treated with CO2 laser and self-made laryngeal dilator. The laryngeal cavity scar was resected as much as possible by using CO2 laser and the laryngeal cavity was exposed by placing laryngeal dilator under general anesthesia.

RESULT

The 24 cases of all were successfully decanulated 1 to 12 months after operation and could breathe freely. One case had second operation and was successfully decanulated 9 months after operation. The follow-up for 1 to 2 years showed all cases speaking well and 3 cases recurrence.

CONCLUSION

The method for treating laryngeal stenosis using CO2 laser and self-mande laryngeal dilator is effective, fewer complication, less invasive, and faster recovery. The laryngeal dilator is made simply and conveniently.

Laser-Assisted Operculectomy

The 10,600-nm CO2 laser is both an efficient and spatially precise photo-thermal ablation device and excellent coagulator because of the close match between its coagulation depth and the diameters of oral soft-tissue capillaries. The ablation of hyperplastic oral soft tissue with the flexible fiber waveguide 10,600-nm CO2 laser is a minimally invasive and typically suture-free surgical modality that ensures dependable treatment. It is, in many respects, superior to most of the alternative treatment options. Its excellent hemostatic abilities and the minimal damage to adjacent healthy tissues make the CO2 laser a perfect surgical tool for treating oral soft-tissue lesions, including the inflamed operculum.

[A case of subglottic osteoma]

A 41 years female patient was hospitalized with hoarseness for three months, without cough, expectoration and dyspnea. The symptom had no relief by application of antibiotics. Electronic laryngoscope showed that there were the grey neoplasms under subglottic anteriou commissure with broad base and slightly rough surface, and bilateral vocal cords were normal; throat CT showed subglottic irregular high density and calcification. The subglottal tumor resection was performed under the general anesthesia and laryngoscope CO2 laser assisted. In the operation, we found that the tumor was hard with surface of thin mucosa tissue, and there was white bone tissue under it. The removing tumor was about 0. 8 cm X 0. 6 cm X 0. 3 cm and was diagnosed as subglottic osteoma by pathologic examine. There was no recurrence in three months follow-up.

20 mA bidirectional laser triggering in planar devices based on vanadium dioxide thin films using CO(2) laser

By utilizing a CO₂ laser centered at ~10.6 μm as an optical stimulus, we demonstrated bidirectional laser triggering in a two-terminal planar device based on a highly resistive vanadium dioxide (VO₂) thin film. The break-over voltage of the VO₂-based device was measured as large as ~294.8 V, which resulted from the high resistivity of insulating VO₂ grains comprising the thin film and the large electrode separation of the device. The bidirectional current switching of up to 20 mA was achieved by harnessing the dramatic resistance variation of the device photo-thermally induced by the laser illumination. The transient responses of laser-triggered currents were also analyzed when laser pulses excited the device at a variety of pulse widths and repetition rates. In the transient responses, a maximum switching contrast between off- and on-state currents was measured as ~7067 with an off-state current of ~2.83 μA, and rising and falling times were measured as ~30 and ~16 ms, respectively, for 100 ms laser pulses.

Effect of engraving speeds of CO₂ laser irradiation on In-Ceram Alumina roughness: a pilot study

OBJECTIVES

The aim of the study was to determine the effect of CO₂ laser on surface roughness of In-Ceram-Alumina-ceramic.

MATERIALS AND METHODS

Four aluminum-oxide ceramic disc specimens were prepared of In-Ceram Alumina. Discs received CO₂ laser irradiation with different engraving speeds (100, 400, 600 and 800 mm/min) as a surface treatment. The roughness of the surfaces was measured on digital elevation models reconstructed from stereoscopic images acquired by scanning-electron-microscope. Surface roughness data were analyzed with One-Way-Analysis-of-Variance at a significance level of p<0.05.

RESULTS

There was no significant difference between the roughness values (p=0.82). Due to higher laser durations, partial melting signs were observed on the surfaces. Tearing, smearing and swelling occurred on melted surfaces. Swelling accompanying melting increased the surface roughness, while laser power was fixed and different laser engraving speeds were applied.

CONCLUSION

Although different laser irradiation speeds did not affect the roughness of ceramic surfaces, swelling was observed which led to changes on surfaces.

Expression of p27 and PTEN and clinical characteristics in early laryngeal squamous cell carcinoma and their correlation with recurrence

Laryngeal squamous cell carcinoma is a common malignant tumor of otolaryngeal region. At present, effective treatment of laryngeal squamous cell carcinoma still depends on surgery and radiotherapy. In recent years, application of CO2 laser resection in the treatment of stage T1 glottic carcinoma can remove the tumor completely and reduce the injury of laryngeal tissues. But recurrence still happened in some postoperative patients. Here, we selected 131 patients to compare the therapeutic effects of CO2 laser resection and traditional split laryngeal surgery on the early laryngeal cancer, examined the expression of p27 and PTEN by immunohistochemistry in early laryngeal squamous cell carcinoma tissues in correlation to clinical outcome. After two years follow-up 14/85 (16.5%) of CO2 laser treatment group presented with local recurrence (recurrent group), while that of split laryngeal surgery group was 6/46 (13.0%). There was no statistical significance in recurrence rate between the two groups (P>0.05). 10 of all the 111 (9.0%) non-recurrent patients did not follow the doctor's advice to quit smoking after the operation, while 12 in the 20 (60.0%) recurrent patients did not; the difference between the two groups was statistically significant (P<0.01). The positive rates of p27 were 80.2% (105/131) and 43.5% (57/131), and that of PTEN were 83.2% (109/131) and 48.9% (64/131) in the cancer adjacent tissues (negative surgical margin tissues) and in laryngeal carcinoma tissues, respectively (P<0.001). The expression rates of p27 and PTEN in laryngeal carcinoma tissues of the recurrent group were 20.0% (4/20), 10.0% (2/20) and that in non recurrent group were 47.7% (53/111) and 55.9% (62/111), respectively, with a significant difference (P<0.001). In addition, the expression of p27 and PTEN in tumor resected marginal tissues of the recurrence group was 50.0% (10/20), 40.0% (8/20) and that in non recurrence group was 85.6% (95/111) and 91.0% (101/111), respectively; the difference was also statistically significant between both groups (P<0.001). In conclusion, there is no statistically significant difference in tumor recurrence rate between CO2 laser surgery and traditional split laryngeal surgery. Postoperative recurrence is closely related to resume smoking. The recurrence rate of p27 and/or PTEN-negative patients was higher than that of the positive ones,that should be followed up closely after treatment.

Breaking DNA strands by extreme-ultraviolet laser pulses in vacuum

Ionizing radiation induces a variety of DNA damages including single-strand breaks (SSBs), double-strand breaks (DSBs), abasic sites, modified sugars, and bases. Most theoretical and experimental studies have been focused on DNA strand scissions, in particular production of DNA double-strand breaks. DSBs have been proven to be a key damage at a molecular level responsible for the formation of chromosomal aberrations, leading often to cell death. We have studied the nature of DNA damage induced directly by the pulsed 46.9-nm (26.5 eV) radiation provided by an extreme ultraviolet (XUV) capillary-discharge Ne-like Ar laser (CDL). Doses up to 45 kGy were delivered with a repetition rate of 3 Hz. We studied the dependence of the yield of SSBs and DSBs of a simple model of DNA molecule (pBR322) on the CDL pulse fluence. Agarose gel electrophoresis method was used for determination of both SSB and DSB yields. The action cross sections of the single- and double-strand breaks of pBR322 plasmid DNA in solid state were determined. We observed an increase in the efficiency of strand-break induction in the supercoiled DNA as a function of laser pulse fluence. Results are compared to those acquired at synchrotron radiation facilities and other sources of extreme-ultraviolet and soft x-ray radiation.

Nor R. Enhanced photoluminescence and Raman properties of Al-Doped ZnO nanostructures prepared using thermal chemical vapor deposition of methanol assisted with heated brass

Vapor phase transport (VPT) assisted by mixture of methanol and acetone via thermal evaporation of brass (CuZn) was used to prepare un-doped and Al-doped zinc oxide (ZnO) nanostructures (NSs). The structure and morphology were characterized by field emission scanning electron microscopy (FESEM) and x-ray diffraction (XRD). Photoluminescence (PL) properties of un-doped and Al-doped ZnO showed significant changes in the optical properties providing evidence for several types of defects such as zinc interstitials (Zni), oxygen interstitials (Oi), zinc vacancy (Vzn), singly charged zinc vacancy (VZn-), oxygen vacancy (Vo), singly charged oxygen vacancy (Vo+) and oxygen anti-site defects (OZn) in the grown NSs. The Al-doped ZnO NSs have exhibited shifted PL peaks at near band edge (NBE) and red luminescence compared to the un-doped ZnO. The Raman scattering results provided evidence of Al doping into the ZnO NSs due to peak shift from 145 cm-1 to an anomalous peak at 138 cm-1. Presence of enhanced Raman signal at around 274 and 743 cm-1 further confirmed Al in ZnO NSs. The enhanced D and G band in all Al-doped ZnO NSs shows possible functionalization and doping process in ZnO NSs.

Fabrication of an inexpensive and high efficiency microphotoreactor using CO2 laser technique for photocatalytic water treatment applications

In this study, a micro-photoreactor with catalyst-immobilized micro-channels was designed and fabricated using CO2 laser as a simple and inexpensive technique. The micro-photoreactor is composed of an array of micro-channels, a quartz plate, and an array of UV-LEDs. The micro-channels with the dimension of 400 µm width, 50 µm depth, and 80 cm length were inscribed on a flat plate of poly(methyl methacrylate) (PMMA). The illuminated specific surface area for the designed micro-reactor was calculated to be 25000 m(-1). To examine the performance of miniaturized photoreactor, the photocatalytic degradation of 4-Nitrophenol as a refractory pollutant was investigated. The effects of operational variables on the performance of micro-photoreactor were studied. Higher photocatalytic degradation is obtained for low flow rates, high light intensities, long micro-channels lengths, and low inlet concentrations. Also, the performance of micro-photoreactor was examined in the presence of different types of TiO2 catalysts with an average particle size between 5 and 27 nm (such as P25, PC500, Merck, and UV100) and textile dyes with different chemical structures (such as Acid Orange 7, Acid Violet 19, Basic Red 46, Methyl Orange, and Malachite Green). Finally, the reusability of miniaturized photoreactor was evaluated and the results showed satisfactory stability and reusability for the designed micro-reactor in the photocatalytic degradation of organic pollutants.

Linkage and anomeric differentiation in trisaccharides by sequential fragmentation and variable-wavelength infrared photodissociation

Carbohydrates and their derivatives play important roles in biological systems, but their isomeric heterogeneity also presents a considerable challenge for analytical techniques. Here, a stepwise approach using infrared multiple-photon dissociation (IRMPD) via a tunable CO2 laser (9.2-10.7 μm) was employed to characterize isomeric variants of glucose-based trisaccharides. After the deprotonated trisaccharides were trapped and fragmented to disaccharide C2 fragments in a Fourier transform ion cyclotron resonance (FTICR) cell, a further variable-wavelength infrared irradiation of the C2 ion produced wavelength-dependent dissociation patterns that are represented as heat maps. The photodissociation patterns of these C2 fragments are shown to be strikingly similar to the photodissociation patterns of disaccharides with identical glycosidic bonds. Conversely, the photodissociation patterns of different glycosidic linkages exhibit considerable differences. On the basis of these results, the linkage position and anomericity of glycosidic bonds of disaccharide units in trisaccharides can be systematically differentiated and identified, providing a promising approach to characterize the structures of isomeric oligosaccharides.

[Age-related peculiarities of thymus reaction to the exposure to helium-neon laser and injured muscle alloplasty with the muscle tissue from the animals of the same age]

Histological, cytological and morphometric changes in the thymus of 1 month-old, adult (3-4 months-old) and old (24-30 months-old) rats (24 animals in each group) were studied during muscle regeneration after the alloplasty of the injured area with the muscle tissue from the animal of the same age. Muscles of the donor or recipient were subjected to the course of preliminary irradiation with He-Ne laser (dose: 4.5-5.4 J/cm2 for each extremity; total dose of 9.0-10.8 J/cm2 per animal). It was shown that the exposure of gastrocnemius muscles that were prepared for the operation to He-Ne laser radiation decreased morpho-functional activity of the thymus in young, adult and old recipient rats the before surgery. This was demonstrated by its weaker reaction to the allograft during the early time intervals after surgery. The observed effect was more pronounced with the increasing age of an animal.

Carbon dioxide laser for detrusor tunnel creation in robot-assisted laparoscopic extravesical ureteral reimplant

OBJECTIVE

Demonstrate and report initial results using a carbon dioxide (CO2) laser for detrusor tunnel creation in robot-assisted laparoscopic extravesical ureteral reimplant (RALUR).

METHODS

Retrospective chart review was performed for cases of RALUR from 2011 to 2014. Patients undergoing complex reconstruction (ureteral tailoring, dismembered reimplant, concomitant ureteroureterostomy), and those who had incomplete follow-up were excluded. Variables, including use of the CO2 laser, were collected and correlated with outcomes.

RESULTS

23 patients representing 40 ureteral units were included for analysis. A CO2 laser was used in 9/23 (39%) patients and 16/40 (40%) ureteral units. Intraoperative mucosotomy was reported in 3/14 (21%) patients for the electrocautery group and 1/9 (11%) patients for the CO2 laser group. Resolution of VUR was observed in 11/14 (79%), and 9/9 (100%) of patients for the electrocautery group and the CO2 laser group, respectively. Two complications were identified in the electrocautery group of patients: ileus (Clavien 2), and transient bilateral ureteral obstruction requiring placement of ureteral stents (Clavien 3B). There were no complications in the CO2 laser group.

CONCLUSIONS

Creation of the detrusor tunnel with a CO2 laser is safe and effective, and is associated with a lower rate of failure and complication in this cohort.

[Objective evaluation of CO2 laser in the treatment of Tis--T glottic carcinoma after operation for voice rehabilitation]

OBJECTIVE

To objectively evaluate the voice rehabilitation status in different period after treatment of Tis--T1 glottic carcinoma by CO2 laser with voice parameters.

METHOD

A retrospective review of 41 cases with Tis--T1 glottic carcinoma treated by CO2 laser was performed, 23 cases were stage Tis (Tis group) and 18 cases with stage T1N0M0 (T1 group). The range of excision of the lesion by CO2 laser was according to the different stages of the tumor, and ensured theoperation negative margin was by intraoperative frozen pathological examination. We tested and compared the actual voice (coritaine F0, Jitter, Shimmer, NNE and MPT) of 30 cases of healthy middle-aged and old male(normal group) and all the patients at one day prior to operation, three months, six months and one year after operation respectively, which was to evaluate the voice rehabilitation status in different period after operation objectively.

RESULT

Postoperative pathological examination revealed, 23 cases were squamous epithelium severe atypical hyperplasia, 16 cases were well differentiated squamous cell carcinoma, and 2 cases were moderately differentiated squamous cell carcinoma. Palatoglossal arch mucosal tear occurred in 3 patients. Respiratory difficulties were not seen in all cases, and normal oral feeding was obtained in all cases in postoperative three days. All patients were followed up for one year. There was statistical significance in F0, Jitter, Shimmer of both Tis group and T1 group after operation in different periods(P<0.05). But there was no statistical significance in NNE and MPT between six months and one years after operation in the two groups(P>0.05).

CONCLUSION

CO2 laser surgery is an effective treatment for early glottic carcinoma. Postoperative vocal function was improved in varying degrees, and voice quality gradually improved with the rehabilitation time. Partly objective parameters reflecting the vocal function gradually stabilized after half a year after operation.

[Evaluate the related factors of recurrence after carbon dioxide laser in treatment of early glottic carcinoma]

OBJECTIVE

To analyze the recurrencerelative factors of early glottic carcinoma after carbon dioxide laser treatment.

METHOD

A retrospective analysis of 134 early glottic carcinoma patients' clinical data was taken to analyze the relationships between recurrence and gender, age, pathologic degree, T stage, involvement of anterior commissure and involvement of thyroarytenoid muscle.

RESULT

Recurrent ratio of well-differentiated, middle-differentiated and poorly-differentiated squamous cell carcinoma were 11.83%, 18.42% and 33.33% (P > 0.05) respectively. Recurrent ratio of T1a, T1b, T2 were 13.24%, 18.92%, 23.08% (P > 0.05) respectively. The recurrent rate was 33.33% of tumors offended the anterior commissure, versus 5.43% with no involvement of anterior commissure (P < 0.01). The recurrent rate was 59.09% of tumors offended the thyroarytenoid muscle, versus 5.36% with no involvement of thyroarytenoid muscle (P < 0.01). Unvaried and multivariate analysis indicated that the involvement of anterior commissure and the involvement of thyroarytenoid muscle were the factors of recurrence.

CONCLUSION

Recurrence of early glottic carcinoma after carbon dioxide laser treatment is effected by the involvement of anterior commissure and the involvement of thyroarytenoid muscle. Resection can be performed conservatively according to evaluation of macroscopic tumour extension.

[Clinical analysis of the treatment for benign tumor of external auditory canal by carbon dioxide laser under microscope]

OBJECTIVE

To investigate the treatment for benign tumor of external auditory canal by carbon dioxide laser under microscope.

METHOD

Ten cases of benign tumor of external auditory canal were treated by carbon dioxide laser under microscope. The curative effects and complications were observed.

RESULT

Ten cases of benign tumor of external auditory canal were satisfied after operation without any complications. There were no recurrences during 3 months to 2 years of follow up.

CONCLUSION

The operation for benign tumor of external auditory canal by carbon dioxide laser under microscope was easy, safe and effective.

[Clinical study on vocal cords spontaneous rehabilitation after CO2 laser surgery]

OBJECTIVE

To study the spontaneous rehabilitation and phonation quality of vocal cords after different types of CO2 laser microsurgery.

METHOD

Surgical procedures based on Remacle system Type I, Type II, Type III, Type IV and Type V a respectively. Three hundred and fifteen cases with hoarseness based on strobe laryngoscopy results were prospectively assigned to different group according to vocal lesions apperence,vocal vibration and imaging of larynx CT/MRI. Each group holded 63 cases. The investigation included the vocal cords morphological features,the patients' subjective feelings and objective results of vocal cords.

RESULT

There are no severe complications for all patients in perioperative period. Vocal scar found in Type I ,1 case; Type II, 9 cases ;Type III, 47 cases; Type IV, 61 cases and Type Va 63 cases respectively after surgery. The difference of Vocal scar formation after surgery between surgical procedures are statistical significance (χ2 = 222.24, P < 0.05). Hoarseness improved after the surgery in 59 cases of Type I , 51 cases of Type II, 43 cases of Type III, 21 cases of Type IV and 17 cases of Type Va. There are statistically significance (χ2 = 89.46, P < 0.05) between different surgical procedures. The parameters of strobe laryngoscope: there are statistical significance on jitter between procedures (F 44.51, P < 0.05), but without difference within Type I and Type II (P > 0.05). This happened in shimmer parameter and the maximum phonation time (MPT) as jitter. There are no statistical significance between Type IV and Type Va on MPT (P > 0.05).

CONCLUSION

Morphological and functional rehabilitation of vocal cord will be affected obviously when the body layer is injured. The depth and range of the CO2 laser microsurgery are the key factors affecting the vocal rehabilitation.

[Suspension laryngoscopic surgery for laryngotracheal stenosis of 32 cases]

OBJECTIVE

To investigate the efficacy of suspension laryngoscopic surgery for benign laryngotracheal stenosis (LTS).

METHODS

Thirty-two patients (aged from 5 to 70 years with a median of 36 years) with benign LTS were studied retrospectively who were treated by suspension laryngoscopic surgery with or without assistance of CO₂ Laser for LTS. Stents were placed in 17 cases. Among 32 patients, 13 cases were with LST in Cotton I, 8 cases in Cotton II, and 11 cases in Cotton III; 23 were with single level narrow, and 9 cases with multi-level narrow; the average narrow length was 1.3 cm and the average diameter at maximum stenosis was 0.5 cm; and 19 cases underwent tracheostomy before surgery.

RESULTS

Follow-up period ranged from 1 to 18 years with median time of 10 years. Twenty-six patients (81.2%) were successfully decannulated with good airway patency and effective phonation. Six cases failed and 1 case of them was changed to open surgery. Among 17 cases with stent placement, 4 cases were applied additionally with T tube (effective rate of 50.0%), 1 case with laryngeal keel, 12 cases with stents alone (effective rate of 66.7%). Stent-related complications occurred in 2 cases. Patients with cotton I-II had a successful rate of 100% (21/21), while patients with Cotton III showed poor effectiveness (5/11), with a statistical significant difference between two groups (χ² = 14.098, P = 0.001). The patients with single level LTS were successfully treated by suspension laryngoscopic surgery with 100% successful rate (23/23), while the patients with multi-level LTS showed poor effectiveness (3/9), with a statistical significant difference between two groups (χ² = 18.872, P = 0.000) .

CONCLUSIONS

Suspension laryngoscopic microsurgery can treat single level LTS with good results and also can be used as a pre-surgery in treatment of multi-level LTS with the virtue of minimal trauma and short recovery time. Application of stents can be helpful for suspension laryngoscope surgery for LST.

Note: Magnification of a polarization angle with a Littrow layout brazed grating

A new method to magnify a small polarization angle with brazed gratings has been developed. In the method, difference in diffraction efficiency for S and P polarization components is used. The magnification dependence on the incident angle can be small by arranging the grating in Littrow layout. A magnification with a factor ~2.7 has been demonstrated for a 10.6 μm CO2 laser beam as expected from a calculation. The method is applicable in many polarimetry fields.

[Preliminary experiences of endoscopic CO₂ laser cauterization for treatment of congenital pyriform sinus fistula]

OBJECTIVE

To evaluate the effectiveness of endoscopic CO₂ laser cauterization (ECLC) as a definitive treatment of congenital pyriform sinus fistula (CPSF).

METHODS

Eleven patients with CPSF underwent ECLC between January 2011 to March 2013 at Guangdong General Hospital. Of the 11 patients aging from 20 to 672 months (median: 60 months), there were 4 males and 7 females; 10 lesions located in the left necks and 1 located in the right; 6 untreated previously and 5 recurrent; 10 sinus (with internal opening) and 1 fistula. The presentations included reduplicative neck swelling, pain, or a fistulous opening with purulent discharge at the anterior neck region. Preoperative examinations included barium esophagogram, CT, MRI and so on. Six patients had at least received one time incision and drainage procedure previously. All patients had been treated with antibiotics in acute infection period. After inflammation subsided, the openings of pyriform sinus fistula were confirmed by esophagoscopy and then ECLC on internal opening was routinely performed.Esophagoscopy was carried out again by 3 months later in every patient, the same technique would be performed immediately if the internal opening was not completely closed.

RESULTS

The existence of an orifice in the pyriform fossa was identified by esophagoscopy in 11 patients. In 9 patients, the treatment was successful and the internal opening completely closed after the first ECLC. However, the other 2 patients received the second cauterization 3 months later because of the incomplete close of the internal opening. The average number of treatments was 1.2 times. No complications such as dysphagia, hoarseness occurred with the endoscopic procedure. Both the patients and their families were satisfied with the cervical appearance. All the patients had an uneventful recovery and remained no symptom from 11 to 35 months (median: 24 months).

CONCLUSION

The endoscopic CO₂ laser cauterization is safe, effective, repeatable and minimally invasive, which can be suggested as first-line treatment for congenital pyriform sinus fistula.

[Clinical observation of traumatic granuloma after CO₂ laser cordectomy and laryngopharyngeal reflux]

OBJECTIVE

Through clinical observation of granuloma after CO₂ laser cordectomy under suspensive laryngoscope to discuss the effects of laryngopharyngeal reflux(LPR) to traumatic granuloma.

METHODS

According to the classification of depth and range of CO₂ laser cordectomy, 111 cases were divided into 5 groups, and the incidence of postoperative granuloma of each group was observed. The largest number of the 5 groups was 49 cases of type III CO₂ laser cordectomy which was subdivided into 4 groups according to whether or not laryngopharyngeal reflux and whether or not proton pump inhibitor (PPI) treatment.

RESULTS

In 111 cases, 56 cases (50.5%) developed granuloma after CO₂ laser cordectomy. The incidence of traumatic granuloma after surgery was 10% (1/10), 26.1% (6/23), 53.1% (26/49), 78.6% (11/14), 80.0% (12/15) in I, II, III, IV, V type, respectively. It had statistical significance in chi-square test between 5 kinds of operative classification and the incidences of postoperative granuloma (χ² = 20.32, P < 0.01) and Spearman correlation analysis showed positive correlation between classification of operation and incidences of granuloma (r = 0.44, P < 0.01). According to LPR (-), LPR (+)and PPI (+), PPI (-), the incidence of granuloma had statistical significance in these 4 group patients of 49 type III cases (χ²= 5.83, P < 0.05). The incidence of granuloma after surgery was the lowest in LPR (-) PPI (+) group (30%) and the highest in LPR (+) PPI (-) group (80%), and it showed significant difference (χ² = 6.25, P < 0.05).

CONCLUSIONS

With the increase of removal depth and the range after CO₂ laser cordectomy, it appears rising trend in incidence of granuloma. Laryngopharyngeal reflux and PPI therapy on the incidence of traumatic granuloma has certain influence.

[The influence of low-intensity laser irradiation on the loach embryo cells]

The ultrastructural organization of loach embryo cells (Misgurnus fossilis L) at the stage of the first and the tenth embryo divisions was investigated in the control and under the influence of low intensity helium-neon laser irradiation of 5 min exposure. The effect of laser irradiation led to ultrastructural changes in cell organelles, increasing the number and size of mitochondria, and as a result their shape changes. Under the influence of laser irradiation, the activation of cellular digestion processes took place, the number of vacuoles and lysosomes increased. The results explain the possible mechanism laser irradiation impact at the cellular level.